Industrially, product dimensioning involves the estimation of the amount of space a shipment will occupy in a trailer or warehousing. This approach is precisely used for a variety of applications including product consistency, inventory monitoring, revenue enhancement for the transportation industry and placement onto air-, rail-, and ground-transport vehicles as well as monitoring of cargo.
Dimensioning of objects, such as parcels or bundles thereof located on a pallet etc., involves measuring and capturing an area or volume that the object occupies. Efficient and cost-effective pricing for dimensioning would take into consideration the volumetric weight also known as dimensional weight of an object, which provides values particularly useful in the storage, handling, shipping and invoicing of such objects. This is attributed to the fact that pricing of light weight goods occupying a large volume based on weight only would result in inappropriate pricing in the so-called less-than-truckload (LTL) industry.
Traditionally, dimensioning was carried out manually by way of processes such as manual measurements of the objects followed by manually entering data into a computer system. However, such manual methods are always prone to human errors and may result in either overcharging or undercharging a customer. Subsequently, over time, the LTL industry has incorporated various automatic methods and solutions to dimension objects in warehouses, such as incorporating laser ranging and scanning systems on a conveyor to measure dimensions of parcels. Alternatively, when dimensioning objects that are located on a pallet and transported by a forklift vehicle, the forklift vehicle stops for the static measurement of the object's dimensions in a specific area in or aside of the conveying path, where a scanning system is mounted overhead. For measurement of the object's dimensions during its transportation, sensors can also be installed on the forklift vehicle itself.
U.S. Pat. No. 6,611,787 discloses an apparatus and method to weigh and dimension objects moving along a conveyor. The apparatus involves three identical ultrasonic sensors deployed along a conveyor belt that moves the objects to be dimensioned and each of the three sensors is designated to determine one aspect of the object's dimension namely length, width and height. The patent also mentions the use of an automated guided vehicle (AGV) to move objects past sensors; however, it does not explicitly disclose a method or arrangement of sensors along a path for the same. An aspect of this patent that represents a disadvantage is the use of the conveyor belt to move objects for dimensioning. This particularly implies a slowing down of the flow of operation in a warehouse during the step of dimensioning because the vehicle carrying objects would have to stop to load objects on a conveying belt followed by dimensioning and then reloading them back onto a truck.
Additionally, such conveyor oriented systems can be effective for small parcels that are bundled downstream of the conveyor however, they prove inefficient time-wise when dimensioning larger objects such as those that have to be transported on pallets by a forklift vehicle.
A mobile product-dimensioning system is disclosed in U.S. Pat. No. 7,757,946 allows a vehicle carrying an object to be dimensioned to pass through an enclosure namely a tunnel that has a dimension detection device mounted on it. The system is equipped to measure the dimension and weight of the vehicle with the pallet moving through the tunnel.
While the tunnel dimensioning system overcomes the shortcoming of employing a conveyor belt, one particular disadvantage of such a tunnel passage for dimensioning is that these systems are installed on the floor which leads to an obstruction in the floor space. Such floor installations are prone to damage by moving vehicles which in turn may lead to a slow-down of warehouse operations.
On the other hand, U.S. Pat. No. 6,115,114 discloses an apparatus and method wherein a forklift vehicle carrying an object to be dimensioned is allowed to pass under a mounted laser scanner sensor system. This system does not describe the use of a tunnel or a defined floor-installed passageway. It makes use of three retroreflectors that are mounted along a center line and on top of the moving forklift vehicle and in turn, the laser scanning sensors are mounted in relation to these retroreflectors.
The retroreflectors provide time and space reference for volumetric measurements of the parcel. However, the retroreflectors necessitate a modification of the forklift vehicle.
In view of this, it would be helpful to develop a scanning system that does not involve modifications of transporting machinery.